Prevalence of Diagnosed Diabetes in Adults by Diabetes Type - United States, 2016.

Currently 23 million U.S. adults have been diagnosed with diabetes (1). The two most common forms of diabetes are type 1 and type 2. Type 1 diabetes results from the autoimmune destruction of the pancreas's beta cells, which produce insulin. Persons with type 1 diabetes require insulin for survival; insulin may be given as a daily shot or continuously with an insulin pump (2). Type 2 diabetes is mainly caused by a combination of insulin resistance and relative insulin deficiency (3). A small proportion of diabetes cases might be types other than type 1 or type 2, such as maturity-onset diabetes of the young or latent autoimmune diabetes in adults (3). Although the majority of prevalent cases of type 1 and type 2 diabetes are in adults, national data on the prevalence of type 1 and type 2 in the U.S. adult population are sparse, in part because of the previous difficulty in classifying diabetes by type in surveys (2,4,5). In 2016, supplemental questions to help distinguish diabetes type were added to the National Health Interview Survey (NHIS) (6). This study used NHIS data from 2016 to estimate the prevalence of diagnosed diabetes among adults by primary type. Overall, based on self-reported type and current insulin use, 0.55% of U.S. adults had diagnosed type 1 diabetes, representing 1.3 million adults; 8.6% had diagnosed type 2 diabetes, representing 21.0 million adults. Of all diagnosed cases, 5.8% were type 1 diabetes, and 90.9% were type 2 diabetes; the remaining 3.3% of cases were other types of diabetes. Understanding the prevalence of diagnosed diabetes by type is important for monitoring trends, planning public health responses, assessing the burden of disease for education and management programs, and prioritizing national plans for future type-specific health services.

Relationship of hepatitis C virus infection with diabetes in the U.S. population.

UNLABELLED: An association of hepatitis C virus (HCV) infection with diabetes has been reported in many studies, but few have been population based and applied standard criteria for diabetes diagnosis. We examined this relationship using recent population-based data from the U.S. National Health and Nutrition Examination Survey. Adult participants (15,128) in the 1999-2010 surveys had data on diabetes status and serum HCV antibody (anti-HCV) or HCV RNA. Using American Diabetes Association criteria, diabetes was defined as a health care provider diagnosis, serum hemoglobin A1C (A1C) ≥6.5%, or fasting plasma glucose (FPG) ≥126 mg/dL, prediabetes as A1C 5.7%-<6.5% or FPG 100-<126 mg/dL, and normal glucose as A1C <5.7% and FPG <100 mg/dL. Odds ratios (ORs) for diabetes and prediabetes, comparing persons with HCV infection to those without, were adjusted for demographics, BMI, C-reactive protein, smoking, drinking, and blood transfusion before 1992. Among participants without diabetes, we compared mean insulin resistance (IR), estimated using homeostasis model assessment (HOMA-IR), by HCV status. The overall prevalence of anti-HCV+ was 1.7%, of HCV RNA(+) 1.1%, of diabetes 10.5%, and of prediabetes 32.8%. The prevalence of diabetes and prediabetes did not differ by HCV status. In multivariate-adjusted analysis, diabetes remained unassociated with anti-HCV (OR, 1.0; 95% confidence interval [CI]: 0.6-1.7) or with HCV RNA (OR, 1.1; 95% CI: 0.6-1.9). In contrast, elevated alanine aminotransferase and gamma glutamyltransferase activities were associated with diabetes regardless of HCV status. HOMA-IR was not associated with HCV markers in unadjusted or multivariate-adjusted analyses (P > 0.05). CONCLUSION: In the U.S. population, HCV was not associated with diabetes or with IR among persons with normal glucose. Previously reported relationships of HCV with diabetes were possibly attributable to the effect of elevated liver enzymes.

Leukocyte telomere length and diabetes status, duration, and control: the 1999-2002 National Health and Nutrition Examination Survey.

BACKGROUND: Studies investigating the association between telomere length and diabetes have been inconsistent, and there are few data available investigating the associations of telomere length with diabetes duration and control. We evaluated the relationship of leukocyte telomere length with diabetes, and the relationship of leukocyte telomere length with diabetes duration and poor glucose control among people with diabetes. METHODS: We used data from the 1999-2002 National Health and Nutrition Examination Survey, a representative sample of the US civilian non-institutionalized population. In 3921 participants, leukocyte telomere length was measured and diabetes status was determined based on a previous diagnosis, hemoglobin A1c ≥ 6.5 %, or fasting glucose ≥ 126 mg/dL. RESULTS: The odds ratios (95 % confidence intervals) of diabetes associated with the first, second, and third quartile of leukocyte telomere length, compared to the highest quartile, was 2.09 (1.46-2.98), 1.74 (1.30-2.31), and 1.08 (0.76-1.54), respectively (p-trend < 0.01), in unadjusted models and 0.74 (0.48-1.14), 0.91 (0.61-1.34), and 0.87 (0.59-1.29), respectively (p-trend = 0.20), in multivariable adjusted models. Among participants with diabetes, unadjusted and adjusted leukocyte telomere length was not associated with diabetes duration or glucose control based on an hemoglobin A1c < 7 or < 8 % (all p > 0.05). CONCLUSIONS: In this study of the US general population, leukocyte telomere length was not associated with diabetes status, diabetes duration, or diabetes control.

Associations between trends in race/ethnicity, aging, and body mass index with diabetes prevalence in the United States: a series of cross-sectional studies.

BACKGROUND: The increase in the prevalence of diabetes over the past few decades has coincided with an increase in certain risk factors for diabetes, such as a changing race/ethnicity distribution, an aging population, and a rising obesity prevalence. OBJECTIVE: To determine the extent to which the increase in diabetes prevalence is explained by changing distributions of race/ethnicity, age, and obesity prevalence in U.S. adults. DESIGN: Cross-sectional, using data from 5 NHANES (National Health and Nutrition Examination Surveys): NHANES II (1976-1980), NHANES III (1988-1994), and the continuous NHANES 1999-2002, 2003-2006, and 2007-2010. SETTING: Nationally representative samples of the U.S. noninstitutionalized civilian population. PATIENTS: 23 932 participants aged 20 to 74 years. MEASUREMENTS: Diabetes was defined as a self-reported diagnosis or fasting plasma glucose level of 7.0 mmol/L (126 mg/dL) or more. RESULTS: Between 1976 to 1980 and 2007 to 2010, diabetes prevalence increased from 4.7% to 11.2% in men and from 5.7% to 8.7% in women (P for trends for both groups < 0.001). After adjustment for age, race/ethnicity, and body mass index, diabetes prevalence increased in men (6.2% to 9.6%; P for trend < 0.001) but not women (7.6% to 7.5%; P for trend = 0.69). Body mass index was the greatest contributor among the 3 covariates to the change in prevalence estimates after adjustment. LIMITATION: Some possible risk factors, such as physical activity, waist circumference, and mortality, could not be studied because data on these variables were not collected in all surveys. CONCLUSION: The increase in the prevalence of diabetes was greater in men than in women in the U.S. population between 1976 to 1980 and 2007 to 2010. After changes in age, race/ethnicity, and body mass index were controlled for, the increase in diabetes prevalence over time was approximately halved in men and diabetes prevalence was no longer increased in women. PRIMARY FUNDING SOURCE: Centers for Disease Control and Prevention and National Institutes of Diabetes and Digestive and Kidney Diseases.

Prevalence of and Trends in Diabetes Among Adults in the United States, 1988-2012.

IMPORTANCE: Previous studies have shown increasing prevalence of diabetes in the United States. New US data are available to estimate prevalence of and trends in diabetes. OBJECTIVE: To estimate the recent prevalence and update US trends in total diabetes, diagnosed diabetes, and undiagnosed diabetes using National Health and Nutrition Examination Survey (NHANES) data. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional surveys conducted between 1988-1994 and 1999-2012 of nationally representative samples of the civilian, noninstitutionalized US population; 2781 adults from 2011-2012 were used to estimate recent prevalence and an additional 23,634 adults from 1988-2010 were used to estimate trends. MAIN OUTCOMES AND MEASURES: The prevalence of diabetes was defined using a previous diagnosis of diabetes or, if diabetes was not previously diagnosed, by (1) a hemoglobin A1c level of 6.5% or greater or a fasting plasma glucose (FPG) level of 126 mg/dL or greater (hemoglobin A1c or FPG definition) or (2) additionally including 2-hour plasma glucose (2-hour PG) level of 200 mg/dL or greater (hemoglobin A1c, FPG, or 2-hour PG definition). Prediabetes was defined as a hemoglobin A1c level of 5.7% to 6.4%, an FPG level of 100 mg/dL to 125 mg/dL, or a 2-hour PG level of 140 mg/dL to 199 mg/dL. RESULTS: In the overall 2011-2012 population, the unadjusted prevalence (using the hemoglobin A1c, FPG, or 2-hour PG definitions for diabetes and prediabetes) was 14.3% (95% CI, 12.2%-16.8%) for total diabetes, 9.1% (95% CI, 7.8%-10.6%) for diagnosed diabetes, 5.2% (95% CI, 4.0%-6.9%) for undiagnosed diabetes, and 38.0% (95% CI, 34.7%-41.3%) for prediabetes; among those with diabetes, 36.4% (95% CI, 30.5%-42.7%) were undiagnosed. The unadjusted prevalence of total diabetes (using the hemoglobin A1c or FPG definition) was 12.3% (95% CI, 10.8%-14.1%); among those with diabetes, 25.2% (95% CI, 21.1%-29.8%) were undiagnosed. Compared with non-Hispanic white participants (11.3% [95% CI, 9.0%-14.1%]), the age-standardized prevalence of total diabetes (using the hemoglobin A1c, FPG, or 2-hour PG definition) was higher among non-Hispanic black participants (21.8% [95% CI, 17.7%-26.7%]; P < .001), non-Hispanic Asian participants (20.6% [95% CI, 15.0%-27.6%]; P = .007), and Hispanic participants (22.6% [95% CI, 18.4%-27.5%]; P < .001). The age-standardized percentage of cases that were undiagnosed was higher among non-Hispanic Asian participants (50.9% [95% CI, 38.3%-63.4%]; P = .004) and Hispanic participants (49.0% [95% CI, 40.8%-57.2%]; P = .02) than all other racial/ethnic groups. The age-standardized prevalence of total diabetes (using the hemoglobin A1c or FPG definition) increased from 9.8% (95% CI, 8.9%-10.6%) in 1988-1994 to 10.8% (95% CI, 9.5%-12.0%) in 2001-2002 to 12.4% (95% CI, 10.8%-14.2%) in 2011-2012 (P < .001 for trend) and increased significantly in every age group, in both sexes, in every racial/ethnic group, by all education levels, and in all poverty income ratio tertiles. CONCLUSIONS AND RELEVANCE: In 2011-2012, the estimated prevalence of diabetes was 12% to 14% among US adults, depending on the criteria used, with a higher prevalence among participants who were non-Hispanic black, non-Hispanic Asian, and Hispanic. Between 1988-1994 and 2011-2012, the prevalence of diabetes increased in the overall population and in all subgroups evaluated.

Association of bilateral oophorectomy and body fatness in a representative sample of US women.

OBJECTIVE: Preclinical studies suggest that abrupt hormone deprivation caused by oophorectomy, leads to obesity and its metabolic sequelae. The purpose of the current study was to examine the association between oophorectomy and body fatness in a nationally representative sample of women. METHODS: The association between prior oophorectomy and nine adiposity measures was examined using data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994). The analytic population included cancer-free women age 40 or older (N=3549) who underwent standardized body measurements and reported on whether or not they had a bilateral oophorectomy. Multivariate linear and polytomous logistic regressions were used to evaluate the association of oophorectomy with multiple measures of adiposity. RESULTS: Mean percent body fat, skinfold thickness, waist circumference and body mass index were significantly higher in women with oophorectomy before age 40 compared to those with intact ovaries, but no difference was observed in women with oophorectomy at an older age. Women who underwent an early oophorectomy were nearly three times more likely than women with intact ovaries to have percent body fat in the highest tertile compared to the lowest tertile (OR=2.82, 95% CI 1.39-5.75). Excluding hormone therapy (HT) users yielded stronger associations. CONCLUSION: Bilateral oophorectomy in young women is strongly associated with an increase in percent body fat, a well-established risk factor for cancer and other chronic diseases. Measuring body fat in addition to BMI may provide a more comprehensive assessment of adiposity in these women.

Glycated hemoglobin and cancer incidence and mortality in the Atherosclerosis in Communities (ARIC) Study, 1990-2006.

Diabetes is a risk factor for many cancers; chronic hyperglycemia is hypothesized to be, in part, explanatory. We evaluated the association between glycated hemoglobin, a time-integrated glycemia measure, and cancer incidence and mortality in nondiabetic and diabetic men and women. We conducted a prospective study of 12,792 cancer-free participants attending the second visit (1990-1992) of the Atherosclerosis Risk in Communities (ARIC) Study. We measured glycated hemoglobin in whole-blood samples using HPLC. Incident cancers were ascertained from registries and hospital records through 2006. We estimated multivariable-adjusted hazard ratios (HR) of cancer incidence and mortality for nondiabetic participants with values ≥ 5.7% (elevated), nondiabetic participants with <5.0% (low) and diabetic participants all compared with nondiabetic participants with 5.0-5.6% (normal). We ascertained 2,349 incident cancer cases and 887 cancer deaths. Compared with nondiabetic women with normal glycated hemoglobin, nondiabetic women with elevated values had an increased risk of cancer incidence (HR:1.24; 95% CI:1.07,1.44) and mortality (HR:1.58; 95% CI:1.23,2.05) as did diabetic women (incidence, HR:1.30; 95% CI:1.06,1.60, mortality, HR:1.96; 95% CI:1.40,2.76). Nondiabetic women with low values also had increased risk. Diabetic women with good glycemic control (<7.0%) had a lower cancer risk than those with higher values. Glycated hemoglobin in nondiabetic and diabetic men, and diabetes were not statistically significantly associated with total cancer risk. Our findings support the hypothesis that chronic hyperglycemia, even in the nondiabetic range, increases cancer risk in women. Maintaining normal glycated hemoglobin overall, and good glycemic control among diabetic adults, may reduce the burden of cancer, especially in women.

Serum sex steroid hormones and frailty in older American men of the Third National Health and Nutrition Examination Survey (NHANES III).

OBJECTIVE: To determine whether frailty is associated with circulating total and free testosterone, total and free estradiol, and sex hormone-binding globulin (SHBG) in older men. METHODS: With NHANES III data of 461 men aged 60 years and older, we used logistic regression to analyze the associations between serum concentrations of sex steroid hormones, SHBG and frailty. Participants meeting any three or more of the five frailty criteria were classified as "frail", all others were considered as non-frail. RESULTS: 2.5% of men were frail. Men with SHBG ≥66 nmol/L had three times the odds of frailty (OR = 2.97; 95% CI 1.28-6.86) compared to men with SHBG <66 nmol/L. Men with free testosterone levels below 243 pmol/L had an increased odds of frailty (OR = 3.92; 95% CI 1.29-11.89). None of these associations was statistically significant after additionally adjusting for body mass index, smoking and history of cardiovascular diseases (CVD). Total testosterone, and total and free estradiol serum levels were not statistically significantly associated with frailty. CONCLUSIONS: In this US nationally representative study of older men, low free testosterone and high SHBG serum levels were associated with a significantly increased odds of frailty after adjustment for age and race/ethnicity. These associations may, however, be explained by confounding due to obesity, smoking, and the higher prevalence of CVD in frail men or by low hormones or high SHBG mediating the association between obesity, smoking, CVD and frailty.

Association of serum α-tocopherol with sex steroid hormones and interactions with smoking: implications for prostate cancer risk.

BACKGROUND: Vitamin E may protect against prostate cancer, possibly only in smokers and, we hypothesize, through altered sex steroid hormones. A controlled trial in smokers showed that sex hormone levels were inversely associated with baseline serum α-tocopherol and decreased in response to vitamin E supplementation. The vitamin E-hormone relation is understudied in non-smokers. METHODS: Serum sex steroid hormones and α-tocopherol were measured for 1,457 men in NHANES III. Multivariable-adjusted geometric mean hormone concentrations by α-tocopherol quintile were estimated. RESULTS: We observed lower mean testosterone, estradiol, and SHBG concentrations with increasing serum α-tocopherol (Q1 = 5.5 and Q5 = 4.6 ng/ml, p-trend = 0.0007; Q1 = 37.8 and Q5 = 33.1 pg/ml, p-trend = 0.02; Q1 = 38.8 and Q5 = 30.6 pg/ml, p-trend = 0.05, respectively). Interactions between serum α-tocopherol and exposure to cigarette smoke for total testosterone, total estradiol, and SHBG were found with the inverse relation observed only among smokers. CONCLUSIONS: Results from this nationally representative, cross-sectional study indicate an inverse association between serum α-tocopherol and circulating testosterone, estradiol, and SHBG, but only in men who smoked. Our findings support vitamin E selectively influencing sex hormones in smokers and afford possible mechanisms through which vitamin E may impact prostate cancer risk.

Body fatness and sex steroid hormone concentrations in US men: results from NHANES III.

OBJECTIVE: Obesity is associated with a variety of chronic diseases, including cancer, which may partly be explained by its influence on sex steroid hormone concentrations. Whether different measures of obesity, i.e., body mass index (BMI), waist circumference, and percent body fat were differentially associated with circulating levels of sex steroid hormones was examined in 1,265 men, aged 20-90+ years old, attending the morning examination session of the Third National Health and Nutrition Examination Survey (NHANES III). MATERIALS AND METHODS: Serum hormones were measured by immunoassay. Weight, height, and waist circumference were measured by trained staff. Percent body fat was estimated from bioelectrical impedance. Multivariate linear regression was used to estimate associations between body fatness measures and hormone levels. RESULTS: Total and free testosterone and sex hormone binding globulin concentrations decreased, whereas total and free estradiol increased with increasing BMI, waist circumference, and percent body fat (all p trend < 0.05). The magnitude of change in these hormones was similar for a one-quartile increase in each body fatness measure. CONCLUSION: Measured BMI, waist circumference, and percent body fat led to similar inferences about their association with hormone levels in men.

The prevalence of low sex steroid hormone concentrations in men in the Third National Health and Nutrition Examination Survey (NHANES III).

BACKGROUND: Physiologic processes during ageing leading to multi-morbidity and diseases that increase risk of premature death may be influenced by ageing-associated changes in endogenous hormone production. OBJECTIVE: To evaluate the decline in sex steroid hormone levels across age and estimate the number of US men 40+ years old who may have low hormone levels. DESIGN: We measured serum testosterone, oestradiol and sex hormone binding globulin by immunoassay in 1351 men 20+ years old in Third National Health and Nutrition Examination Survey. We estimated free hormones by mass action. RESULTS: Free testosterone declined most rapidly with age (a 2% decline in geometric mean concentration occurred after ageing 1·3 years), followed by total testosterone (2·4 years), free oestradiol (4·1 years) and total oestradiol (8·1 years). These hormone changes with age translated into 25·0% and 30·2% of men 70+ years old having low total (which we defined as <10·4 nm) and free (<0·17 nm) testosterone, respectively, and 8·3% and 23·9% having low total (<73·4 pm) and free (<2·2 pm) oestradiol. Using population size projections between the 2000 and 2010 Censuses, we estimated that 8·4 (95% CI 4·7-12·2), 6·2 (3·1-9·2) and 6·0 (3·1-9·0) million men 40+ years old may have low total testosterone, free testosterone and free oestradiol, respectively. The prevalences were only modestly lower in men without prevalent chronic diseases. CONCLUSION: Although no consensus exists for defining low hormone levels in ageing men, a substantial number of US men may have low sex steroid hormone levels, possibly putting them at risk for adverse health consequences and premature death.

Cognitive function among older adults with diabetes and prediabetes, NHANES 2011-2014.

AIMS: To determine the association between diabetes status, glycemia, and cognitive function among a national U.S. sample of older adults in the 2011-2014 National Health and Nutrition Examinations Surveys. METHODS: Among 1,552 adults age ≥ 60 years, linear and multivariable logistic regressions were used to determine the association between diabetes status (diabetes, prediabetes, normoglycemia) and cognitive function [Consortium to Establish a Registry for Alzheimer's Disease-Word Learning (CERAD W-L), Animal Fluency test, Digit Symbol Substitution Test (DSST)]. RESULTS: Overall, diabetes was associated with mild cognitive dysfunction. In age-adjusted models, adults with diabetes had significantly poorer performance on the delayed and total word recalls (CERAD W-L) compared to those with normoglycemia (5.8 vs. 6.8 words; p = 0.002 and 24.5 vs. 27.6 words; p < 0.001, respectively); the association was non-significant after adjusting for cardiovascular disease. Among all adults, cognitive function scores decreased with increasing HbA1c for all assessments, but remained significant in the fully adjusted model for the Animal Fluency and DSST [beta coefficient = -0.44;-1.11, p < 0.05, respectively]. As measured by the DSST, the proportion with cognitive impairment was significantly higher for older adults with HbA1c ≥ 8.0% (≥64 mmol/mol) vs. HbA1c < 7.0% (<53 mmol/mol) (14.6% vs. 6.3%, p = 0.04). CONCLUSIONS: Dysglycemia, as measured by HbA1c, was associated with poorer executive function and processing speed.

Sex steroid hormone concentrations and risk of death in US men.

The association of sex hormone levels with mortality over a median of 16 years of follow-up was evaluated in a prospective cohort study. The study included 1,114 US men who participated in phase 1 (1988-1991) of the Third National Health and Nutrition Examination Survey Mortality Study and had no history of cardiovascular disease or cancer at baseline. Multivariable adjusted hazard ratios for all-cause mortality associated with a decrease in hormone concentration equal to the difference between the 90th and 10th percentiles of the sex hormone distributions were estimated by using proportional hazards regression. The hazard ratios associated with low free testosterone and low bioavailable testosterone levels were 1.43 (95% confidence interval (CI): 1.09, 1.87) and 1.52 (95% CI: 1.15, 2.02), respectively, for follow-up between baseline and year 9; they were 0.94 (95% CI: 0.51, 1.72) and 0.98 (95% CI: 0.56, 1.72), respectively, for follow-up between year 9 and year 18. Men with low free and bioavailable testosterone levels may have a higher risk of mortality within 9 years of hormone measurement. Future studies should be conducted to fully characterize the association of low free and bioavailable testosterone concentrations and mortality in men and to describe the mechanism underlying the association.

Association of serum cholesterol and cholesterol-lowering drug use with serum sex steroid hormones in men in NHANES III.

PURPOSE: Low cholesterol levels and statin drugs may protect against prostate cancer with a worse prognosis. Their protective mechanism is unknown, but has been hypothesized to be related to cholesterol's role as a sex steroid hormone precursor. We evaluated whether serum testosterone and estradiol differ by cholesterol or cholesterol-lowering drug use. MATERIALS AND METHODS: Testosterone and estradiol were measured for 1,457 male participants in the Third National Health and Nutrition Examination Survey. We estimated multivariable-adjusted geometric mean hormone concentration by quintiles of cholesterol concentration and by cholesterol-lowering drugs use. RESULTS: Across quintiles of cholesterol, testosterone level did not differ (mean, 95% confidence interval (CI); Q1: 5.25, 5.02-5.49, Q5: 5.05, 4.76-5.37 ng/ml; p-trend = 0.32), whereas estradiol levels were lower (Q1: 38.7, 36.9-40.5; Q5: 33.1, 31.8-34.5 pg/ml; p-trend < 0.0001). Neither testosterone (no: 5.12, 4.94-5.30, yes: 4.91, 4.33-5.57 ng/ml, p = 0.57) nor estradiol (no: 35.9, 34.8-37.1; yes: 33.9, 29.4-39.2 pg/ml; p = 0.39) differed by cholesterol-lowering drugs use. CONCLUSION: Testosterone did not differ by cholesterol or cholesterol-lowering drug use. Estradiol was lower in men with higher cholesterol, but did not differ by cholesterol-lowering drug use. Our results suggest that the lower risk of advanced prostate cancer among statin users is not readily explained by a cholesterol-mediated effect of statins on sex hormone levels.

Comparison of several survey-based algorithms to ascertain type 1 diabetes among US adults with self-reported diabetes.

INTRODUCTION: Defining type of diabetes using survey data is challenging, although important, for determining national estimates of diabetes. The purpose of this study was to compare the percentage and characteristics of US adults classified as having type 1 diabetes as defined by several algorithms. RESEARCH DESIGN AND METHODS: This study included 6331 respondents aged ≥18 years who reported a physician diagnosis of diabetes in the 2016-2017 National Health Interview Survey. Seven algorithms classified type 1 diabetes using various combinations of self-reported diabetes type, age of diagnosis, current and continuous insulin use, and use of oral hypoglycemics. RESULTS: The percentage of type 1 diabetes among those with diabetes ranged from 3.4% for those defined by age of diagnosis <30 years and continuous insulin use (algorithm 2) to 10.2% for those defined only by continuous insulin use (algorithm 1) and 10.4% for those defined as self-report of type 1 (supplementary algorithm 6). Among those defined by age of diagnosis <30 years and continuous insulin use (algorithm 2), by self-reported type 1 diabetes and continuous insulin use (algorithm 4), and by self-reported type 1 diabetes and current insulin use (algorithm 5), mean body mass index (BMI) (28.6, 27.4, and 28.5 kg/m2, respectively) and percentage using oral hypoglycemics (16.1%, 11.1%, and 19.0%, respectively) were lower than for all other algorithms assessed. Among those defined by continuous insulin use alone (algorithm 1), the estimates for mean age and age of diagnosis (54.3 and 30.9 years, respectively) and BMI (30.9 kg/m2) were higher than for other algorithms. CONCLUSIONS: Estimates of type 1 diabetes using commonly used algorithms in survey data result in varying degrees of prevalence, characteristic distributions, and potential misclassification.

Serum selenium and peripheral arterial disease: results from the national health and nutrition examination survey, 2003-2004.

The authors conducted a cross-sectional study of the association of serum selenium with the prevalence of peripheral arterial disease among 2,062 US men and women 40 years of age or older participating in the National Health and Nutrition Examination Survey, 2003-2004. Serum selenium was measured by using inductively coupled plasma-dynamic reaction cell-mass spectrometry. Peripheral arterial disease was defined as an ankle-brachial blood pressure index <0.90. The age-, sex-, and race-adjusted prevalence of peripheral arterial disease decreased with increasing serum selenium (P for linear trend = 0.02), but there was an indication of an upturn in risk in the highest quartile of serum selenium. The fully adjusted odds ratios for peripheral arterial disease comparing selenium quartiles 2, 3, and 4 with the lowest quartile were 0.75 (95% confidence interval: 0.37, 1.52), 0.58 (95% confidence interval: 0.28, 1.19), and 0.67 (95% confidence interval: 0.34, 1.31), respectively. In spline regression models, peripheral arterial disease prevalence decreased with increasing serum selenium levels up to 150-160 ng/mL, followed by a gradual increase at higher selenium levels. The association between serum selenium levels and the prevalence of peripheral arterial disease was not statistically significant, although a U-shaped relation was suggested.

Association of cigarette smoking, alcohol consumption, and physical activity with sex steroid hormone levels in US men.

BACKGROUND: We evaluated the associations of smoking, alcohol consumption, and physical activity with sex steroid hormone concentrations among 1,275 men > or =20 years old who participated in the Third National Health and Nutrition Examination Survey (NHANES III). METHODS: Serum concentrations of testosterone, estradiol, and sex hormone-binding globulin (SHBG) were measured. We compared geometric mean concentrations across levels of smoking, alcohol, and physical activity using multiple linear regression. RESULTS: Current smokers had higher total testosterone (5.42, 5.10, and 5.26 ng/ml in current, former, and never smokers), free testosterone (0.110, 0.102, and 0.104 ng/ml), total estradiol (40.0, 34.5, and 33.5 pg/ml), and free estradiol (1.05, 0.88, and 0.84 pg/ml) compared with former and never smokers (all p < or = 0.05). Men who consumed > or =1 drink/day had lower SHBG than men who drank less frequently (31.5 vs. 34.8 nmol/l, p = 0.01); total (p-trend = 0.08) and free testosterone (p-trend = 0.06) increased with number of drinks per day. Physical activity was positively associated with total (p-trend = 0.01) and free testosterone (p-trend = 0.05). CONCLUSIONS: In this nationally representative sample of men, smoking, alcohol, and physical activity were associated with hormones and SHBG, thus these factors should be considered as possible confounders or upstream variables in studies of hormones and men's health, including prostate cancer.

Cadmium levels in urine and mortality among U.S. adults.

BACKGROUND: Cadmium exposure has been associated with increased all-cause, cancer, and cardiovascular disease mortality. However, studies investigating this association have included participants with considerably higher levels of cadmium than those found in the general population. OBJECTIVE: We aimed to evaluate the association of creatinine-corrected urinary cadmium levels with all-cause and cause-specific mortality in the U.S. general population. METHODS: We analyzed the relationship between cadmium measured in 13,958 adults who participated in the Third National Health and Nutrition Examination Survey in 1988-1994 and were followed through 31 December 2000, and all-cause, cancer, cardiovascular disease, and coronary heart disease mortality. RESULTS: The geometric mean levels of urinary cadmium per gram of urinary creatinine in study participants were 0.28 and 0.40 microg/g for men and women, respectively (p < 0.001). After multivariable adjustment, including smoking, a major source of cadmium exposure in nonoccupationally exposed populations, the hazard ratios [95% confidence interval (CI)] for all-cause, cancer, cardiovascular disease, and coronary heart disease mortality associated with a 2-fold higher creatinine-corrected urinary cadmium were, respectively, 1.28 (95% CI, 1.15-1.43), 1.55 (95% CI, 1.21-1.98), 1.21 (95% CI, 1.07-1.36), and 1.36 (95% CI, 1.11-1.66) for men and 1.06 (95% CI, 0.96-1.16), 1.07 (95% CI, 0.85-1.35), 0.93 (95% CI, 0.84-1.04), and 0.82 (95% CI, 0.76-0.89) for women. CONCLUSIONS: Environmental cadmium exposure was associated with an increased risk of all-cause, cancer, and cardiovascular disease mortality among men, but not among women. Additional efforts are warranted to fully explain gender differences on the impact of environmental cadmium exposure.